I've been doing some reading about heavy AFs and clots after my last shocker lasting 2 full weeks. In my case it is indicative of an anovulatory cycle...because no egg is released, the oestrogen builds and builds with no progesterone to moderate it...AF hits and there's a mega-lining to slough off. Not suggesting this is the case for you, but if you think you're skipping ovulation (for whatever reason) then this can happen (very common in perimenopause when ovulation starts dropping out).